流速对半导体气体传感器响应的影响分析

Influence of Gas Flow on Response of Semiconductor Gas Sensor

半导体气体传感器被广泛应用在电子鼻系统中用于检测可燃性气体。然而,半导体气体传感器对环境变化非常敏感,从而影响电子鼻识别目标气体浓度的精度。文章通过实验研究了气体流速对传感器响应曲线及特征参数的影响,研究结果表明,流过传感器的流速对传感器的动态响应和稳态响应都有影响。流速越大,传感器的响应时间和恢复时间越短,灵敏度越高,基线电压越小,不同传感器的稳态响应电压受流速的影响趋势不同。流量小于200 sccm时,传感器受流速变化的影响较大,当流量大于500 sccm以后,传感器受流速变化的影响已越来越小。

Semiconductor gas sensors are widely used in the e-nose systems to detect combustible gas.However,semiconductor gas sensors are sensitive to the change of environment around,which has an impact on the recognition precision of the e-nose.This paper studied the influence of gas flow on the response curves and the feature parameters of semiconductor gas sensor by experiments,and the results show that the flow velocity of the gas around the sensors has an influence on both the dynamic response and the steady response of the sensors,increasing the flow velocity,the response time and the recovery time will decrease,the sensitivity will increase and the baseline voltage will decrease,and the flow velocity has different influence on the maximum response value to different sensors.Below 200 sccm,the variation of flux has relatively large influence on the response of the sensors,while above 500 sccm,the influence is small.